Vicki B. Gaubeca, director of the ACLU's Regional Center for Border Rights in New Mexico, said human rights organizations across the country met in September with Border Patrol leaders in Washington, D.C.

"[CBP officials] are going over their training guidelines, over their criteria for use of force," she said, adding that the agency's convoluted complaint system needs addressing. "Even if you had the courage to complain, you would have to figure out whom you make that complaint to."

Pedro Rios, of the American Friends Service Committee, said his organization is part of a larger network of border groups, including the ACLU of New Mexico, talking to the federal agency about creating a border-abuse-documentation system so groups can track the information they collect on migrant abuse.

"Can you please explain what steps you're going to be taking to ensure that every individual in custody is treated humanely, and . . . describe what oversight [exists] to prevent abuse of detained immigrants at Border Patrol facilities. I've asked this question before. I've gotten responses. I'm told that changes are being made.

"However, I continue to hear from advocacy groups that go into these facilities and hear complaints from immigrants about their treatment. So, again, this is an area that needs attention immediately."

Bersin gave a standard comment about the agency's taking seriously its "commitment to humane and lawful treatment of all people taken into custody."

And though he briefly discussed the treatment of unaccompanied minors in Border Patrol custody, he did not describe whatever oversight there may be to stop the general abuses documented by border activists.

Roybal-Allard didn't press for an answer, and neither did anyone else.

Cantu chalks up the activists' furor over alleged widespread mistreatment of immigrants to human nature.

"It's almost expected, [that the immigrants] have to hate us, spread as many bad tales about us as they can," the Tucson Sector agent said. "But what about the other stories? What about the immigrant I gave my sandwich to? And it's not just me; agents do it many times. We give them our food and water. I wonder how often they tell that story.

"What about the man I helped pull out of a ravine? His legs were broken after he crashed his car running from us . . . What about the drug smuggler we rescued after bajadores attacked him, stole his drugs, and left him for dead in the desert?"

Human rights groups aren't worried about agents who conduct themselves professionally. They acknowledge there are plenty of them. They want steps taken to weed out dishonest and abusive agents.

A group of about two dozen local and national organizations pushing for changes in America's immigration policies sent a joint letter to the chairman of the U.S. House Judiciary Committee in June after the death of Hernandez Rojas at the San Diego-Tijuana border:

"A meaningful security cannot coexist with law enforcement cultures of impunity and recklessness; we urge you to use your oversight responsibilities to ensure our nation's Customs and Border Patrol officers are adequately trained."

Because, as the number of agents has dramatically increased along the nation's Southwest border, the letter continues, "The training, oversight, and accountability measures for [. . .] agents have not kept pace."

Perhaps it was this lack of training, lack of supervision that led a Border Patrol agent to square his stance, pull back his arm, and swing at Daniel—even as the immigrant walked toward the agent with his hands in the air.

The agent's fist swooshed past Daniel's face, narrowly missing his jaw. But the federal officer drove his elbow into the left side of the immigrant's mouth.

Stunned by the blow, Daniel collapsed face-first on the rocky desert floor. The agent, winded and sweaty, pressed his foot on the back of Daniel's head, quickly grabbed his hands, and cuffed his wrists tightly behind his back.

Dianna, Daniel's wife, stood crying next to the irate agent. She watched as her husband struggled to get to his feet without use of his arms.

"I said, 'Get up!'" the agent barked, and then delivered another booted blow to the downed man.

Daniel groaned. He tried to move faster, inched his knees toward his chest, and finally stood. His head and body throbbed with pain, and the metallic taste of blood filled his mouth. His heart ached as he looked at his weeping wife.

The three walked toward a transport vehicle nearby. Daniel thought about the now-wasted days that he and a pack of fellow immigrants had spent walking through the desert. He regretted running when the agents arrived.